High blood pressure drugs increase risk of strokes

Drugs that have been recommended as a first choice treatment for high blood pressure could be increasing the risk of patients suffering strokes, a major new study has revealed. People taking beta-blockers were at a 16% greater risk of stroke than if they took other anti-high blood pressure drugs, according to the findings. One particular beta-blocker, atenolol, was found to be associated with a 26% higher stroke risk than other drugs.

There was no difference between the treatments in relation to heart problems.

A team of researchers led by Professor Lars Hjalmar Lindholm, from Umea University Hospital, Sweden, pooled together data from 13 trials involving more than 105,000 patients.

In a further investigation involving 27,500 patients from seven studies, the scientists found that those taking beta-blockers were only 19% less likely to have a stroke than those having no treatment at all.

This was about half the benefit expected from previous trials. Beta-blockers work by blocking the activity of a messenger chemical called noradrenaline. The effect is to widen the arteries and slow down the heart.

Writing in The Lancet, Prof Lindholm's team said beta-blockers had been widely used in the treatment of high blood pressure, or hypertension, for three decades. They were still recommended as "first-line drugs in hypertension guidelines". I.L.